Environmental contaminants are toxic and undesirable compounds that can endanger human health and the survivorship of life on Earth. Thus, their removal from the environment has become a hot topic of numerous research works [1]. The application of advanced materials and new applied technologies gives very important results in various fields, such as in improving human life, eliminating environmental pollution, and environmental remediation. There is great interest in producing efficient photocatalytic compounds that can remove a wide spectrum of toxic pollutants to remediate the environment. Photocatalysis technology has undergone ultra-fast development during the past several decades and has been widely applied in many fields, such as photo-synthesis, pollutant treatment, and other chemical- or energy-related processes [2,3]. Photocatalysis is accepted as a beneficial and environmentally friendly solution for the removal of undesirable contaminants. This environmentally friendly technology uses non-hazardous reactants that do not lead to the problem of environmental contamination. The results of energy-saving, simplicity, and reproducibility are also important characteristics of this efficient technology [4]. Its most substantial advantage is the capability to mineralize a wide variety of contaminants. In recent years, a remarkable number of scientific papers have been reported on the utilization of oxide nanostructures to eliminate environmental pollution [5,6,7]. The energy gap for the nanophotocatalysts was determined, making the nanocomposites favorable for removing contaminants. With a completely environmentally friendly method in the photocatalytic process, utilizing sunlight in the presence of photocatalytic compounds, poisonous contaminants can be oxidized or even degraded [8,9]. Optimization studies for the photocatalytic decomposition of each contaminant demonstrated that the best performance could be achieved at a specific amount of contaminant and nanocatalyst [10].

Two major problems related to population growth, urbanization, and economic growth, environmental and public health concerns, as well as the depletion of non-renewable resources, are caused by the problem of inadequate waste management. According to the available data, the total world production of natural and synthetic rubber amounted to over 25 million tons [11], of which about 60% was used for the production of car tires. Preliminary estimates suggest that the total stock of waste tires is around 100 million tons, with only about 10% being recoverable [12,13].

Tires are a specific category of waste, as they are very durable and almost non-degradable [14,15], which is why they are a major environmental problem [16,17]. Waste tire management methods depend on various factors, such as country characteristics, industry development, and population. According to some projections, worldwide, waste raised from tires amounts to 1.5 billion tons/year and by the end of 2025, is expected to be more than 2.5 billion tons [18].

Results of certain studies conclude that Europe, Asia, and North America generate 90% of the total amount of scrap tires [19,20]. Eastern Europe has traditionally had disposal fees at a lower level than Western Europe, and lower safety standards have enabled the intensification of the trade of used tires and their reuse. A necessary condition for putting things under control is to increase disposal fees and strengthen safety regulations [21]. At the same time, some research suggests that the model of “manufacturer and importer responsibility” for tire recycling should be applied in other countries as well, as it has proven successful in most European countries [22,23].

Waste tire management includes a set of measures for the collection, takeover and transport, storage, and treatment of waste tires. After the end of the life cycle, numerous recycling alternatives (pyrolysis, retread, shredding, compacting rubberized concrete, crumbing, reclaiming, rubber modified asphalt) are carried out in the process of waste tire treatment, which creates conditions for using waste tires for energy purposes. European directives do not cover part of the management of waste tires, as is the case with electrical and electronic waste, waste batteries, and accumulators. Although the EU has banned the disposal of tires in landfills since 2009, most countries do not have specific legislation on waste tire collection. However, a number of countries are trying to find ways to extend their life cycle. Improperly collected and disposed waste tires can endanger the environment by polluting the air, soil, and water.

Additionally, due to mechanical abrasion, car tires release particles in the environment, and many studies point to the problem of car tires as a source of microplastics in the environment [24,25,26]. As the release of this abrasive material is not possible in the near future [27], the results of some recent research suggest that emission reduction of non-exhaust emission source [28] and tire wear and tear [29,30] should be given more prominence on the political agenda [31].

The problem of waste tires is rising from year to year, especially in countries in transition. The policy and mechanism of waste reuse and recycling is based on the rational use of resources, and not uncontrolled one-time use, or uncontrolled ignition and improper disposal in the case of tires. The combustion of tires produces many toxic substances [32,33,34] and is extremely harmful to all three media in the environment, suggesting that the problems are not only environmental, but also health-related. They are very hazardous waste and drastically impair air quality through the emission of combustion products [35], which requires an expensive air emission control system [36]. Atmospheric toxic pollutants emitted from burning tires directly endanger public health and safety [37,38], and cause various types of mild to severe diseases [39,40,41].

In order to alleviate the energy crisis and environmental degradation, it has become imperative to use technology to obtain energy from unconventional sources, such as municipal and/or industrial waste, in which used tires have a special place. Due to their high calorific value, tires are used as an energy source in some countries (controlled incineration) where incinerators contain the necessary systems for the purification and treatment of gases. As waste tires have a higher energy content than coal, scrap tire recycling can significantly contribute to reducing GHG emissions [42]. However, this is not the primary option in tire treatment. The literature suggests several processes for used tires, analyzes the environmental and economic aspects of these processes, and investigates different management schemes for used tires [43]. As the need for the recovery and recycling of waste is increasingly emphasized, efforts are being made for the development of new technologies for used tire treatment [44,45,46,47,48].

2. Current Status of Waste Tire Management: The Case of Montenegro